Beyma 12BR70

• Sensitivity (1W, 1m, infinite baffle) SPL1W 90.4dB
• Frequency response 35 - 4000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 31Hz
• Mechanical quality factor QMS 4.40
• Electrical quality factor QES 0.56
• Total quality factor QTS 0.50

Large signal parameters

• Maximum linear excursion xmax 8mm
• Maximum excursion before damage xlim 26mm
• Air volume displaced at xmax VD 432cm³
• Power handling P 125W
• Program power Pmax 250W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.6Ω
• Inductance (1kHz) LE 0.8mH
• VC Diameter 50.8mm
• Winding height HVC 19mm

Magnet

• Force factor Bl 12.1N/A
• Motor constant Bl/√RE 5.11N/√W
• Air gap height HAG 7mm

Diaphragm

• Effective diameter 262mm
• Effective area SD 540cm²
• Moving mass MMS 74g
• Moving mass (without air load) MMD 65.2g

Suspensions

• Stiffness KMS 2.9N/mm
• Compliance CMS 345µm/N
• Equivalent volume to the compliance VAS 142L
• Mechanical resistance RMS 3.3N·s/m

Dimensions

• Nominal diameter 12″
• 300mm
• Overall diameter 312mm
• Baffle cutout diameter 278mm
• Overall depth 134mm
• Volume occupied by the driver (estimated) 1.8L
• Net weight 3.6kg